Headlights Wiring Upgrade

I'm not sure about the 140 , I've seen someone on this forum with lights tucked in behind the grill. I really want to compare the light output between mine and dedmanwalking or NachaLuva to see the improvement, increasing power to the factory setup to work at optimum power might be much better bang for buck then adding extra driving lights!
 
Thanks. You may well be right. Or a combination of these factors.

One would imagine that the electrical engineers at Fuji should be able manage to run adequate power cable to the relays, FCOL. Specially after making this vehicle for about ten years ...
 
Yea just the normal ones i think, i had 100 watt ones in my corolla, kicking myself i didnt remove them before the tow truck took it for scrap metal, I might bring mine down on the weekend then and my camera and take some comparision photos
 
Ratbag said:
Does the SF have glass headlight lenses? Rear shell?
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The SF lenses are definitely galss, not sure bout the reflector. I've had my 130/90W globes in for 2yrs now with no probs :biggrin:

idw said:
Has anyone done a before and after photo of the light output before ad after putting the loom in? Would be great for those thinking about the upgrade
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I've been meaning to do this, will have to one day as the difference is huge! :lildevil:
 
Ratbag said:
One would imagine that the electrical engineers at Fuji should be able manage to run adequate power cable to the relays, FCOL. Specially after making this vehicle for about ten years ...
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Ok i did some testing on my headlights today and have got the following. I've been thinking about why upgrading the loom works if the lights only need 12v? Required more reading then i thought, and remembering some stuff i learnt working as a stage technician
So to begin with:

SF stock light setup p/s 60/55 globes

Voltage open circuit 13.2v

Voltage with lights on 12.6 volts @ 5.2amps 65.5watts (high beams) on a 15amp fused circuit with 1mm2 wire.

Thats about all that circuit can take in the way of amps reliably

Now the H4 standard is rated at 12volts and can operate up to 14.5v. 5% increase in voltage puts out rougly 15% more light, so operating at 14v compared to 12 is best case an increase of 45% overall light output (real world is never really like that thought) at more than likely a decreased life expectancy of the globe. A by product of increasing voltage is a decrease in current and an increase in resistance (ohms law) meaning the lights end up drawing less in power from the battery, the increase in resistance results in an increase in heat output from the bulb

So why isn't the full voltage of the battery during charge going to the lights when the alternator puts out 14volts to the batter? Because subaru is inline with the EU headlight standards which says 100% is to be measured at 13.2volts for car head lights, which is exactly what my SF's open curcuit voltage is. Just adding the globe increases the resistence of the circuit resulting in a drop of voltage.

Or the short version

Pro's of wiring in an upgraded headlight loom

  • increased light output
  • decreased current draw (when engine is running)
  • capability to adequatly supply power to high wattage globes
Con's of wiring upgrade

  • increased heat from lights
  • decrease in life expectancy of the globes (good quality globes though shouldn't see this as the H4 standard states life expectancy to be calculated at 14v i doubt cheapies would bother doing it properly)
  • cost (its cheaper to leave them alone)
  • increase in UV (yellows poly headlight lenses faster)
Compared to a good set of driving lights, it's cheaper to upgrade the loom. Most of the cons are avoided using good qaulity components and having glass lenses.

EDIT: Ignore the "pro" of decreased power consumption think i got that wrong
 
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Well done indeed, Id. You get a "Purple Kookaburra" for that effort, mate :iconwink: :biggrin:.

It seems that the Fuji electrical engineers knew precisely what they were about, as I suspected would be the case.

So the polycarbonate lenses are a huge plus. Basically unbreakable in normal road use, vs. hugely expensive to replace a glass lens.

When I bought Roo1, I nearly died at the cost of $60 or so for a pair of headlight protectors, until the salesman told me what a new headlight unit cost. About $300 each, IIRC. That was in 1994. I repaired those protectors about 4 times over my ownership of Roo1. Make that at least $1,200 saved by the headlight protectors (assuming new parts, at 1994 prices).

The small downside of these newer polycarb lenses is that it is not a good idea to overheat them by upping the output of the standard globes, or by fitting higher wattage globes.

So if I can't get the lights to give me acceptable light on the road, buy a nudge bar, and jump for $300-400 worth of Lightforce driving lights.

Thanks for all your work, and your detailed write-up.
If I could make your post into a permanent bookmark here, I would. The only way would be to copy your post into a new thread, and sticky that thread. I will think about it. Thanks again.
 
NachaLuva did the wiring dia and testing which is the important bit, the dia alone makes diy upgrading headache free if anything his dia and 'how to' should be a sticky. The feedback on having high wattage globes in not damaging the SF reflector relieves the worry of it melting

Theres always just spending $400 on nighvision goggles instead of lights? I've no idea if the newer poly lenses will melt from high watt globes, halogen lights give off UV and headlight plastics have UV stabilisers so they dont yellow as quickly. I've no clue if the higher output would make a noticable difference say in 5 years to what it would be normally, But the sun gives off alot for UV radiation then the lights going to and most cars live outside anyway.
https://offroadsubarus.com/member.php?u=2617
 
Ratbag said:
When I bought Roo1, I nearly died at the cost of $60 or so for a pair of headlight protectors, until the salesman told me what a new headlight unit cost. About $300 each, IIRC. That was in 1994.
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I know how you feel mate.

However, after having at least 4x headlights saved by the protectors, I'm very happy with the price I paid for my headlight protectors :cool:
They were worth every cent :)


Regards
Mr Turbo
 
Nice write up idw many valid points there.

My understanding of ohms law didnt agree with this though;
idw said:
A by product of increasing voltage is a decrease in current and an increase in resistance (ohms law) meaning the lights end up drawing less in power from the battery, the increase in resistance results in an increase in heat output from the bulb
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idw said:
Or the short version

Pro's of wiring in an upgraded headlight loom

  • decreased current draw (when engine is running)
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And after some measurement today I think this point is most likely incorrect.

Here are the current/voltage specs from one globe in my car (130W globe)

Engine off;
globe voltage: 11.6V
Globe current 8.1A
Globe power (volts x Amps): 94W
Globe resistance: 1.432 ohms

Engine running;
globe voltage: 14V
Globe current 9.1A
Globe power (volts x Amps): 127W
Globe resistance: 1.5385 ohms

The way I understand ohms law is that it can only be used to calculate change in current for a change in voltage if the device (globe in our case) is ohmic (which means its resistance is constant) If the globe was ohmic the current would increase as voltage increases in a linear manner ( I=V(increasing)/R(constant) )

Most globes however are not ohmic so ohms law cant be used in this way.
Globes generally do increase in resistance when additional voltage is applied but this increase is not usually sufficient to stop additional current flow.

I also dont agree with this;

Ratbag said:
It seems that the Fuji electrical engineers knew precisely what they were about, as I suspected would be the case.
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If the circuit was well designed the voltage would be 13.2V with the load applied.

Another interesting discovery from my voltage and current measuring is that you said the globes were rated at 12V. I would assume that would mean that a 130W globe operating at 12V would use 130W of power. My 130W globes only use 100W at 12V and require 14V before they use 130W. These are high quality Phillips rally globes so I would have thought that they would comply to all the required standards....
Maybe H4 globes are made to different but it makes me very happy that I went to an effort to remove almost all voltage drop.

So in short;

  • Upgrading wiring will;
  • supply more voltage to globes
  • Make them use more current (you dont get more light for nothing)
  • Result in brighter globes
  • Provide more efficient lighting? as less power is lost in voltage drops along supply wires
  • Make your globes operate at rated wattage? (assuming they are made to the same standards as my globes)
 
Looks like i missed something DedmanWalkin, i was under that impression halogen lights work differently to an incandescent light partly from the tungsten filament. I'll check later but the results you've got show the opposite of my assumption.

I'm planning on upgrading the wiring on mine soon as well.
 
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I think halogen lights are just an incandescent light on steroids. The halogen just allows them to run at a higher voltage/hotter than they normally would be able to such producing more light.
I also think (definitely could be wrong about this one) that most incandescent bulbs these days use tungsten filaments.

Also that was very interesting stuff about the 13.2V standard you found. Why on earth would the not make it a 14-14.5V standard and be done with it....
 
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Your probably right, thinking about it the extra heat from increasing the voltage isn't just energy out of thin air. I might be getting confused at the simple math of it, 12V x 5A = 60watts, vs 14V x 4.3A = 60watts, If i get time i'll get out my power supply and test it.

EDIT: I'm speculating the voltage standard isn't 14v heacause the H4 globe began being used around 1970 and electronics in cars didn't in general have as stable a voltage comming into the system. Give some space for overcharging alternators etc not just blowing the things up. and The EU laws vs. design standards vs manufacturer rarely line up correctly.
 
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Hey everybody, hope this thread is not dead yet.
I just got me some driving lights for my subaru liberty '96.
I had a quick look under the steering wheel today and noticed that all holes going to the engine bay are sealed properly.
Can someone can give me a good advice what might be the best way to put a cable through to the engine bay?
 
ZMaster said:
Hey everybody, hope this thread is not dead yet.
I just got me some driving lights for my subaru liberty '96.
I had a quick look under the steering wheel today and noticed that all holes going to the engine bay are sealed properly.
Can someone can give me a good advice what might be the best way to put a cable through to the engine bay?
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There should be a nice big rubber boot in the firewall drivers side. I used the one near the clutch pedal but it might be different in a liberty. Just find a large rubber boot & poke a LITTLE hole in, just big enough for the wire to squeeze through :iconwink:
 
I switched over to H4 xenon for my headlights. Unbelievable what a light. Took 5600k which is the same color as halogen. Very happy with it and 100% legal here in holland.
 
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